Taps for controlling liquid flow

ABSTRACT

The invention discloses a tap ( 10 ) for controlling liquid flow. The tap ( 10 ) has a tube ( 14 ) with first ( 16 ) and second ( 18 ) opposite open ends, an inlet opening ( 20 ) leading into the tube between the first and second open ends, and an outlet opening ( 16 ) defined by the first open end ( 16 ), which outlet opening ( 16 ) serves as an outlet from the tube ( 14 ). The tap ( 10 ) further includes a first valve seat ( 36 ), formed between the inlet opening ( 20 ) and the outlet opening ( 16 ), and a second valve seat ( 38 ), formed between the inlet opening ( 20 ) and the second open end ( 18 ). A closure member ( 42 ) is sealingly slidably movable in the tube ( 14 ) and is provided with a first circumferential sealing edge ( 60 ), the first sealing edge ( 60 ) being adapted to removably abut against the first valve seat ( 36 ). The closure member ( 42 ) is further provided with a second circumferential sealing edge ( 66 ), the second sealing edge ( 66 ) being adapted to removably abut against the second valve seat ( 38 ).

FIELD OF INVENTION

[0001] The present invention relates to taps for liquid flow control.

BACKGROUND TO INVENTION

[0002] The so-called “bag-in-box” containers are widely used to packagewine, fruit juices and other liquids. The liquid is contained in aflexible pouch of plastics material and the pouch is placed into acardboard box.

[0003] A tap is provided for opening the pouch and enabling controlledamounts of liquid to be dispensed. The entire tap can be secured to thepouch. Alternatively, a gasket or flange can be secured to the pouch andthe tap can be placed loose in the cardboard box.

[0004] The tap should be simple in construction and inexpensive to make.It should not leak or drip and must not permit ingress of air into thebag.

[0005] It is an object of the present invention to provide a tap whichmeets the conditions set out above more successfully than other knowntaps.

SUMMARY OF INVENTION

[0006] According to the invention a tap for controlling liquid flowhaving a tube with first and second opposite open ends, an inlet openingleading into the tube between the first and second open ends, an outletopening defined by the first open end, which outlet opening serves as anoutlet from the tube, includes a first valve seat formed between theinlet opening and the outlet opening; a second valve seat formed betweenthe inlet opening and the second open end; a closure member sealinglyslidably movable in the tube; a first circumferential sealing edgeprovided on the closure member, the first sealing edge being adapted toremovably abut against the first valve seat; and a secondcircumferential sealing edge provided on the closure member, the secondsealing edge being adapted to removably abut against the second valveseat.

[0007] The closure member may be displaceable internally along the tubeto cause the first sealing edge to move across the inlet opening frombetween a first or closed position, in which the first sealing edge ofthe closure member cooperates with the first valve seat to close off theinlet opening from the outlet opening and the second sealing edgecooperates with the second valve seat, into a second or open position inwhich the first and second sealing edges are spaced away from the firstand second valve seats to permit liquid flow through the inlet openinginto the tube and out through the outlet opening, and for closure of theoutlet opening the reverse procedure taking place to cause the closuremember to be moved back into the first or closed position.

[0008] The first valve seat and the first sealing edge may be adapted todeflect the closure member outwardly against the tube, when the closuremember is in the closed position.

[0009] The first and second valve seats may be convexly curved.

[0010] The first valve seat may be provided with a convexly curvedcircumferential protuberance extending approximately half-way across thefirst valve seat.

[0011] The protuberance may be spaced away from an inner wall of thetube.

[0012] The first and second sealing edges may be convexly curved.

[0013] The first sealing edge may be provided with a convexly curvedcircumferential protuberance extending approximately half-way across thefirst sealing edge.

[0014] The protuberance may be located near to an outer wall of theclosure member.

[0015] The first and second sealing edges may be adapted to have a smallcontact area with the first and second valve seats respectively.

[0016] The closure member and the tube may both be resilient, but theclosure member may be less resilient to deformation than the tube.

[0017] A skirt may extend from the first sealing edge of the closuremember towards the open end.

[0018] The skirt may be adapted to be in flush contact with a section ofthe inner wall of the tube when the closure member is in a closedposition.

[0019] The closure member may form part of a plunger knob.

[0020] The tap may include guiding means for rotatably guiding theplunger knob along a spiral path.

[0021] The guiding means may include at least one spiral groove in thetube and at least one protrusion from the plunger knob slidingly engagedin the spiral groove(s).

[0022] Further according to the invention, a tap for controlling liquidflow having a tube with first and second opposite open ends, an inletopening leading into the tube between the first and second open ends, anoutlet opening defined by the first open end, which outlet openingserves as an outlet from the tube, includes a valve seat formed betweenthe inlet opening and the outlet opening; a closure member sealinglyslidably movable in the tube; a circumferential sealing edge provided onthe closure member, the sealing edge being adapted to removably abutagainst the valve seat; and the valve seat and the sealing edge beingadapted to deflect the closure member outwardly against the tube, whenthe closure member is in a closed position.

[0023] The closure member may be displaceable internally along the tubeto cause the sealing edge to move across the inlet opening from betweena first or closed position, in which the sealing edge of the closuremember cooperates with the valve seat to close off the inlet openingfrom the outlet opening, into a second or open position in which thesealing edge is spaced away from the valve seat to permit liquid flowthrough the inlet opening into the tube and out through the outletopening, and for closure of the outlet opening the reverse proceduretaking place to cause the closure member to be moved back into the firstor closed position.

[0024] The tap may include a second valve seat formed between the inletopening and the second open end and a second circumferential sealingedge provided on the closure member being adapted to removably abutagainst the second valve seat.

[0025] The first and second valve seats may be convexly curved.

[0026] The first valve seat may be provided with a convexly curvedcircumferential protuberance extending approximately half-way across thefirst valve seat.

[0027] The protuberance may be spaced away from an inner wall of thetube.

[0028] The first and second sealing edges may be convexly curved.

[0029] The first sealing edge may be provided with a convexly curvedcircumferential protuberance extending approximately half-way across thefirst sealing edge.

[0030] The protuberance may be located near to an outer wall of theclosure member.

[0031] The first and second sealing edges may be adapted to have a smallcontact area with the first and second valve seats respectively.

[0032] The closure member and the tube may both be resilient, but theclosure member may be less resilient to deformation than the tube.

[0033] A skirt extends from the first sealing edge of the closure membertowards the open end.

[0034] The skirt may be adapted to be in flush contact with a section ofthe inner wall of the tube when the closure member is in a closedposition.

[0035] The closure member may form part of a plunger knob.

[0036] The tap may include guiding means for rotatably guiding theplunger knob along a spiral path.

[0037] The guiding means may include at least one spiral groove in thetube and at least one protrusion from the plunger knob slidingly engagedin the spiral groove(s).

BRIEF DESCRIPTION OF DRAWINGS

[0038] The invention will now be described by way of example withreference to the accompanying schematic drawings.

[0039] In the drawings there is shown in:

[0040]FIG. 1 a side view of a tap for liquid flow control in accordancewith the invention;

[0041]FIG. 2 a sectional end view seen along arrows II-II in FIG. 1;

[0042]FIG. 3 on an enlarged scale, a view of the area indicated by arrowIII in FIG. 2; and

[0043]FIG. 4 on an enlarged scale, a view of the area indicated by arrowIV in FIG. 2.

DETAILED DESCRIPTION OF DRAWINGS

[0044] Referring to FIGS. 1 and 2, a tap in accordance with theinvention, generally indicated by reference numeral 10, is shown. Thetap 10 includes a hollow tubular body or barrel 12 having a cylindricaltube 14 with opposite open ends 16 and 18. Part-way along its length,the tube 14 has an integrally formed funnel 20 having a disc-like flange22 and sleeve 24 at one end. The sleeve 24 is of larger diameter thanthe tube 14 and protrudes from the flange 22 opposite to the funnel 20.The sleeve 24 is adapted to be in push-fit with a pouch. The funnel 20serves as an inlet to the tap 10 for liquid contained in the pouch,while the open end 16 serves as an outlet from the tap 10 for theliquid.

[0045] A circular collar 26 protrudes from the tube 14 approximatelymidway along its length.

[0046] The tube 14 has an outer wall 28 and an inner wall 30.

[0047] Between the collar 26 and the open end 18 of the tube 14, thereis a double start spiral groove 32 and 34 formed into the outer wall 28.Each groove 32,34 extends through approximately 180°, i.e. a half turnover its full extent. The spiral grooves 32,34 start near the collar 26and terminate just short of the open end 18 of the tube 14.

[0048] The barrel 12 further includes first and second valve seats 36,38formed into the inner wall 30 of the tube 14. The first valve seat 36 islocated between the funnel and the open end 16. The second valve seat 38is spaced apart from the first valve seat 34 and is located between thefunnel 20 and the open end 18. The valve seats 36,38 will be describedin more detail hereinafter.

[0049] Through the open end 18 of the barrel 12 a plunger knob 40 isfitted onto the tube 14. The plunger knob 40 includes a closure member42, an outer skirt 44, and a radially transverse end wall 46. The skirt44 has two radially inwardly directed protrusions 48,50 on the innersurface thereof. The protrusions 48,50 are respectively slidably locatedin the grooves 32,34.

[0050] The closure member 42 is of generally round cylindrical formhaving an outer wall 52 and an inner wall 54 and midway along its lengthis internally closed by a transverse wall 56. The wall 56 has a conicalrecess 58 on its side facing towards the open end 16. The closure member42, relatively near to its end facing the open end 16 of the barrel 12,is provided with a substantially conically inclined first sealing edge60 being adapted to cooperate with the first valve seat 36, as is shownmore clearly in FIG. 3. The first sealing edge 60 of the closure member42 lies at an angle relative to the outer wall 52, which angle has beendesignated by “α” in FIG. 3. The first valve seat 36 is alsosubstantially conically inclined having an angle relative to the innerwall 30 of the tube 14 identical to the angle

[0051] The first sealing edge 60 is provided with a slight convexlycurved circumferential protuberance 62. The valve seat 36 is alsoprovided with a slight convexly curved circumferential protuberance 64.These convex protuberances 62,64 ensure continuous circumferentialcontact between the first valve seat 36 and the first sealing edge 60when the tap 10 is closed.

[0052] A skirt 61 is provided extending from the first sealing edge 60towards the open end 16. The skirt 61 extends beyond the first valveseat 36 and is adapted to be in flush contact with the section 30.1 ofthe inner wall 30 of the tube 14 when the plunger knob 40 is in theclosed position.

[0053] The closure member 42, approximately mid-way along its length,further has a second sealing edge 66 on its outer wall 52 being adaptedto cooperate with the second valve seat 38, as is shown more clearly inFIG. 4. Both the second valve seat 38 and second sealing edge 66 areconvexly curved in sectional side view to ensure continuouscircumferential contact between the second valve seat 38 and the secondsealing edge 66 when the tap 10 is closed.

[0054] A closure cap 68, having a cylinder 70 and an end wall 72, isfitted onto the plunger knob 40 so as to close off the open end 18.

[0055] When the tap 10 is closed, as shown in FIG. 1, the sleeve 24 andfunnel 20 are filled with liquid, as they are in communication with theinterior of a pouch. When the plunger knob 40 is rotated in ananti-clockwise direction from the position illustrated in FIGS. 1 and 2,axial movement thereof occurs in addition to the turning movement due tosliding co-operation between the grooves 32,34 and the protrusions48,50. Thus the closure member 42 is shifted away from the open end 16.The sealing edges 60,66 of the closure member 42 separate from the valveseats 36,38 and the closure member 42 uncovers the funnel 20. Theplunger knob 40 is now in an open position and flow of liquid occursthrough the funnel 20 into the barrel 12 and through the outlet open end16 out of the tap 10.

[0056] When the plunger knob 40 is rotated in a clockwise direction, theclosure member 42 is moved towards the open end 16, back into theposition shown in FIGS. 1 and 2. As the first sealing edge 60 of theclosure member 42 moves past the funnel 20, the funnel 20 is closed andthere is a wiping action which minimises the possibility of the tap 10dripping after it has been closed. Furthermore, the wiping action of theskirt 61 on the inner wall 30.1 also reduces dripping after the tap 10is closed.

[0057] Thereafter, eventually, the sealing edges 60,66 respectivelyre-engage the valve seats 36,38 to close the open end 16 and to stopflow of liquid through the barrel 12 and the open end 16 entirely. Asthe first sealing edge 60 and the first valve seat 36 are urged intocontact during rotation of the plunger knob 40 towards the closedposition of the tap 10, the first valve seat 36 tends to deflect thefirst sealing edge 60 of the closure member 42 outwardly, therebycausing the outer wall 52 of the closure member 42 to engage against theinner wall 30 of the tube 14. This is allowed by the resiliency of theplastics material used to produce the barrel 12 and the plunger knob 38.The outward deflection of the first sealing edge 60 also causes theskirt 61 into tight flush contact with the inner wall 30.1. This assistsin the prevention of any leakage occurring once the tap 10 is closed.

[0058] Thus there are three seals in action in the vicinity of the firstvalve seat 36 between the interior of the pouch and the open end 16. Thefirst seal exists where the first sealing edge 60 and the first valveseat 36 are in engagement, the second seal exists where the outer wall52 of the closure member 42 engages against the inner wall 30 of thetube 14, and the third seal exists where the skirt 61 is in flushcontact with the inner wall 30.1 of the tub 14. Furthermore, the contactbetween the second sealing edge 66 and the second valve seat 38 preventsany leakage towards the open end 18, between the barrel 12 and theplunger knob 38, caused by capillary forces.

[0059] The portion of the grooves 32,34 which are closest to the collar26, can be of lesser pitch than the remaining portions of the grooves32,34 or can extend circumferentially for a short distance. Thus thereis little or no tendency for the plunger knob 40 to rotate from theposition it is left in when the tap 10 is fully closed.

[0060] If desired, the sealing edges 60,66 and the valve seats 36,38 canbe in engagement before the plunger knob 40 has rotated into itsfurthest closed position.

[0061] The two-start grooves 32,34 can be replaced by a single-startgroove or by a groove having more than two starts.

[0062] There is at all times contact between the closure member 42 andthe tube 14 due to the tight sealing fit of the closure member 42 andthe tube 14. As explained above, the slidable sealing fit of the closuremember 42 in the tube 14, and the length over which these componentscontact, forms a seal such that there is little prospect of leakagebetween the plunger knob 38 and the barrel 12. This seal alsoeffectively minimises leakage when the tap 10 is open.

1. A tap (10) for controlling liquid flow having a tube (14) with first(16) and second (18) opposite open ends, an inlet opening (20) leadinginto the tube between the first and second open ends, an outlet opening(16) defined by the first open end (16), which outlet opening (16)serves as an outlet from the tube (14), the tap (10) being characterizedthereby that it includes a first valve seat (36) formed between theinlet opening (20) and the outlet opening (16); a second valve seat (38)formed between the inlet opening (20) and the second open end (18); aclosure member (42) sealingly slidably movable in the tube (14); a firstcircumferential sealing edge (60) provided on the closure member (42),the first sealing edge (60) being adapted to removably abut against thefirst valve seat (36); and a second circumferential sealing edge (66)provided on the closure member (42), the second sealing edge (66) beingadapted to removably abut against the second valve seat (38).
 2. A tapas claimed in claim 1, characterized thereby that the closure member(42) is displaceable internally along the tube (14) to cause the firstsealing edge (60) to move across the inlet opening (20) from between afirst or closed position, in which the first sealing edge (60) of theclosure member (42) cooperates with the first valve seat (36) to closeoff the inlet opening (20) from the outlet opening (16) and the secondsealing edge (66) cooperates with the second valve seat (38), into asecond or open position in which the first (60) and second (66) sealingedges are spaced away from the first (36) and second (38) valve seats topermit liquid flow through the inlet opening (20) into the tube (14) andout through the outlet opening (16), and for closure of the outletopening (16) the reverse procedure taking place to cause the closuremember (42) to be moved back into the first or closed position.
 3. A tapas claimed in claim 1 or claim 2, characterized thereby that the firstvalve seat (36) and the first sealing edge (60) are adapted to deflectthe closure member (42) outwardly against the tube (14), when theclosure member (42) is in the closed position.
 4. A tap as claimed inany one of the preceding claims, characterized thereby that the first(36) and second (38) valve seats are convexly curved.
 5. A tap asclaimed in any one of the preceding claims, characterized thereby thatthe first valve seat (36) is provided with a convexly curvedcircumferential protuberance (64) extending approximately half-wayacross the first valve seat (36).
 6. A tap as claimed in claim 5,characterized thereby that the protuberance (64) is spaced away from aninner wall (30) of the tube (14).
 7. A tap as claimed in any one of thepreceding claims, characterized thereby that the first (60) and second(66) sealing edges are convexly curved.
 8. A tap as claimed in any oneof the preceding claims, characterized thereby that the first sealingedge (60) is provided with a convexly curved circumferentialprotuberance (62) extending approximately half-way across the firstsealing edge (60).
 9. A tap as claimed in claim 8, characterized therebythat the protuberance (62) is located near to an outer wall (52) of theclosure member (42).
 10. A tap as claimed in any one of the precedingclaims, characterized thereby that the first (60) and second (66)sealing edges arc adapted to have a small contact area with the first(36) and second (38) valve seats respectively.
 11. A tap as claimed inany one of the preceding claims, characterized thereby that the closuremember (42) and the tube (14) are both resilient, but that the closuremember (42) is less resilient to deformation than the tube (14).
 12. Atap as claimed in any one of the preceding claims, characterized therebythat a skirt (61) extends from the first sealing edge (60) of theclosure member (42) towards the open end (16).
 13. A tap as claimed inclaim 12, characterized thereby that the skirt (61) is adapted to be inflush contact with a section (30.1) of the inner wall (30) of the tube(14) when the closure member (42) is in a closed position.
 14. A tap asclaimed in any one of the preceding claims, characterized thereby thatthe closure member (42) forms part of a plunger knob (40).
 15. A tap asclaimed in any one of the preceding claims, characterized thereby thatit includes guiding means (32,34,48,50) for rotatably guiding theplunger knob (40) along a spiral path.
 16. A tap as claimed in claim 15,characterized thereby that the guiding means (32,34,48,50) includes atleast one spiral groove (32,34) in the tube (14) and at least oneprotrusion (48,50) from the plunger knob (40) slidingly engaged in thespiral groove(s) (32,34).
 17. A tap (10) for controlling liquid flowhaving a tube (14) with first (16) and second (18) opposite open ends,an inlet opening (20) leading into the tube (14) between the first (16)and second (18) open ends, an outlet opening (16) defined by the firstopen end (16), which outlet opening (16) serves as an outlet from thetube (14), the tap (10) being characterized thereby that it includes avalve seat (36) formed between the inlet opening (20) and the outletopening (16); a closure member (42) sealingly slidably movable in thetube (14); a circumferential sealing edge (60) provided on the closuremember (42), the sealing edge (60) being adapted to removably abutagainst the valve seat (36); and the valve seat (36) and the sealingedge (60) being adapted to deflect the closure member (42) outwardlyagainst the tube (14), when the closure member (42) is in a closedposition.
 18. A tap as claimed in claim 17, characterized thereby thatthe closure member (42) is displaceable internally along the tube (14)to cause the sealing edge (60) to move across the inlet opening (20)from between a first or closed position, in which the sealing edge (60)of the closure member (42) cooperates with the valve seat (36) to closeoff the inlet opening (20) from the outlet opening (16), into a secondor open position in which the sealing edge (60) is spaced away from thevalve seat (36) to permit liquid flow through the inlet opening (20)into the tube (14) and out through the outlet opening (16), and forclosure of the outlet opening (16) the reverse procedure taking place tocause the closure member (42) to be moved back into the first or closedposition.
 19. A tap as claimed in claim 17 or claim 18, characterizedthereby that it includes a second valve seat (38) formed between theinlet opening (20) and the second open end (18) and a secondcircumferential sealing edge (66) provided on the closure member (42)being adapted to removably abut against the second valve seat (38). 20.A tap as claimed in any one of claims 17 to 19, characterized therebythat the first (36) and second (38) valve seats are convexly curved. 21.A tap as claimed in any one of claims 17 to 20, characterized therebythat the first valve seat (36) is provided with a convexly curvedcircumferential protuberance (64) extending approximately half-wayacross the first valve seat (36).
 22. A tap as claimed in claim 21,characterized thereby that the protuberance (64) is spaced away from aninner wall (30) of the tube (14).
 23. A tap as claimed in any one ofclaims 17 to 22, characterized thereby that the first (36) and second(38) sealing edges are convexly curved.
 24. A tap as claimed in any oneof claims 17 to 23, characterized thereby that the first sealing edge(60) is provided with a convexly curved circumferential protuberance(62) extending approximately half-way across the first sealing edge(60).
 25. A tap as claimed in claim 24, characterized thereby that theprotuberance (62) is located near to an outer wall (52) of the closuremember (42).
 26. A tap as claimed in any one of claims 17 to 25,characterized thereby that the first (60) and second (66) sealing edgesare adapted to have a small contact area with the first (36) and second(38) valve seats respectively.
 27. A tap as claimed in any one of claims17 to 26, characterized thereby that the closure member (42) and thetube (14) are both resilient, but that the closure member (42) is lessresilient to deformation than the tube (14).
 28. A tap as claimed in anyone of claims 17 to 27, characterized thereby that a skirt (61) extendsfrom the first sealing edge (60) of the closure member (42) towards theopen end (16).
 29. A tap as claimed in claim 28, characterized therebythat the skirt (61) is adapted to be in flush contact with a section(30.1) of the inner wall (30) of the tube (14) when the closure member(42) is in a closed position.
 30. A tap as claimed in any one of claims17 to 29, characterized thereby that the closure member (42) forms partof a plunger knob (40).
 31. A tap as claimed in any one of claims 17 to30, characterized thereby that it includes guiding means (32,34,48,50)for rotatably guiding the plunger knob (40) along a spiral path.
 32. Atap as claimed in claim 31, characterized thereby that the guiding means(32,34,48,50) includes at least one spiral groove (32,34) in the tube(14) and at least one protrusion (48,50) from the plunger knob (40)slidingly engaged in the spiral groove(s) (32,34).
 33. A tapsubstantially as hereinbefore described with reference to and asillustrated in the accompanying schematic drawings.